aTalk is an xmpp client designed for android and supports the following features:
* Instant messaging in plain text and End-to-End encryption with OMEMO or OTR
* Implement Jabber VoIP-PBX gateway Telephony allowing PBX phone call via service gateway (experimental)
* SSL Certificate authentication DNSSEC and DANE Security implementation for enhanced secure Connection Establishment
* Omemo encryption is available during multi-user-chat session giving users' maximum privacy and security
* Support multi-user chat in room creation server chat rooms discovery and joining chat room with captcha protection
* Support both voice and video call with ZRTP SDES and DTLS SRTP encryption modes
* Support simultaneous media call and message chat sessions
* Send and receive files for all document types and images with thumbnail preview before file is sent
* Auto accept file transfer request with max file size option
* Support downloadable Stickers Bitmoji and Emoji rich content sharing via Google Gboard
* Unique GPS-Location implementation standalone tool or sending locations to your chosen buddy for real-time tracking or playback animation.
* A 360° street view of your current location may use for self-guided tour. The street view tracks and follows your direction of sight.
* Built-in demo for GPS-Location features
* Integrated photo editor with zooming and cropping user can update the avatar with ease
* Last message correction message carbons and offline messages (omemo)
* Mobile network ping interval self-tune optimization support
* In-Band Registration with captcha support
* Multiple accounts creation
* Multi-language UI support (Bahasa Indonesia English German Russian and Spanish) Others required contribution
* Free and Open Source